UPDATED on December 16, 2014
Most builders assume — and GBA has long reported — that oriented strand board (OSB) is a good air barrier. If a builder uses a high quality tape like Siga Wigluv, Zip System tape, or 3M All Weather flashing tape to seal sheathing seams, OSB wall and roof sheathing can act as a building’s primary air barrier.
Oriented strand board (OSB) gets blamed for a lot of problems that are really the fault of the designers and builders. Part of the problem, of course, is the perrenial confusion between correlation and causality. OSB hit the market as we really started getting serious about insulation and air sealing.
Contractors who specialize in repairing rotten walls won’t run out of work any time soon. The epidemic of wall-rot problems that began more than 20 years ago shows no signs of abating. In fact, wet-wall specialists are often called to investigate problems in developments where most of the homes have rotting walls — and in some cases, these homes are only six years old.
Posted on March 29,2015 by user-756436 in earth tube
The first single-family Passivhaus in the U.S. was completed by Katrin Klingenberg in 2004. Klingenberg’s superinsulated home in Urbana, Illinois includes two unusual features: a ventilation system that pulls fresh outdoor air through a buried earth tube, and walls that include an interior layer of OSB. These details were not invented by Klingenberg; she adopted practices that were commonly used by European Passivhaus builders.
In many areas of the country, hundreds of stucco-clad homes have suffered wall rot. Although building scientists are still researching the causes of wall rot behind stucco, it’s clear that all of these walls got wet and were unable to dry.
Posted on March 29,2015 by user-756436 in cold OSB
During the winter months, wall sheathing is usually cold. Cold sheathing is risky, since it tends to accumulate moisture during the winter. Unless the sheathing can dry out during the summer months, damp sheathing can rot.